Smoking is the leading preventable cause of death in the United States. It is a major cause of cancer and other serious disease, and is by far the leading cause of lung cancer. The proposed study will test a state-of-the- art corporate smoking cessation clinic supplemented by either active or placebo nicotine replacement (transdermal nicotine system). It is hypothesized that active nicotine replacement will lead to a significant reduction in withdrawal symptoms and to improved abstinence. A minimum of 120 subjects from six companies will be randomly assigned to either active or placebo transdermal patch. All subjects will attend a 9 week smoking cessation clinic followed by several assessment sessions. Withdrawal symptom and smoking status data will be collected at each session. Self- reported abstinence will be validated by expired carbon monoxide and saliva cotinine. Twelve month outcome data will be collected independently of SBIR funding. If results are as hypothesized, a widely disseminable corporate program will have been established that for the first time systematically integrates psychological and behavioral intervention. this will lead directly to Phase II research.